SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '55df819ed4966bedef6ad902aa7da0f03c6d5a3c210b5d5adf63eae86fda743e' 
  AND token = 'kM5iCI3U1/H7h/PqnguYO8uLDJTh/2YKAI71aEKZ6h4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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