SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc63ffe65d3e886ed1ff2e8d4a4a3a478fd8a25978975f6a3bb8be03477cf837' 
  AND token = 'TSf2Qz7SROzIzjtDiCLsAmoQjdLxo9TAIXseKkBU8D4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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