SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be7b7dc5fba979de6f6e02e4b2ba617479667aa36076de2ff458524f4c241c59' 
  AND token = '5QGJWLuzLEOiDsv/LvyLU3zeIA21jrcb5AXGrNaEE3o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables