SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ddec05d1753e67cff403cf053db24976b3c42902b3029dca4efcdb2fa43f53e' 
  AND token = 'OkycintXNr6wiHuwnhrI7W2WWqM1Hf/vXOfSRovyvaA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}