SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce242dbcc019ac235c4412360c9b18c982a1d5e6ee7b5672de3a8f02d2fac4f2' 
  AND token = 'qRYYfL/PzEVnwffHbYpwX87yCVGpulFpQZJykQt2ZDU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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