SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '4df21cad4090085b605b1c858574b5373a3c4ab5f77afbd6e6bb57d3abfa1379' 
  AND token = 'lRvY44zTLMQhLNVq8ecFJhMs5VC9dcyIArZleQEuig0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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