SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd20b008fb0e6ef766711adc532da9d5b394192ac4ace0b67fb4f13bdc65bf2ce' 
  AND token = 'iA6mZVRlochkaCyf8nQBx2+3GpnpKqkEocttxqcZHyM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

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