SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '23f55ef063c6fb6a4b489a85e464ba3d6c8f756fb35767c6add50b6fb5d65307' 
  AND token = 'El3hRJ6keEv+VNtz1/SzLUiyT5PFpSVQVKwPoRAqwMw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

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