SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '02350afe713e3cd28a556fdb2ca28ee11ce8170eca4bf1a8daa3c433cf58b125' 
  AND token = 'rQ7R3jucMnJoK9PMTraxgmR9dlvSSJ4zKTCDwvlO2DI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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