SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5e55afbea8b3ebba08371ff779aa587be7464481f818f4971a3ef7ae54030a65' 
  AND token = 'Ay99kJwAC1LeGhbiIcESkzSdg3xclf0/ZYTgRjDcfvY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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