SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b67ef1549b942bd09c43cccc011e7609463a5f488236a8a4984cbca66d42f2f' 
  AND token = '8pjHYrlbqg58e/c7wy4nTvC1Y/ONwCqKmZP5vRyjKa0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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