SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e680cfbf5c40fd149fc35c7ec639ea565c524497eb95c1b2e88d44f3d127246f' 
  AND token = 'Xah/w1Ln+Kn+zOxspzNGwC6BE6ZWYGDEb/QCKzCxtho=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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