SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f411ee5e570bfb435862ce508ffb9107cbbd401faeca6bebf18b552515faf1b3' 
  AND token = 's4kfglgAtsYHofsOpDu2AtYOO2PRfpP8vHjdAC4oreM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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