SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'de64039d7e99a3a7a253dbb4fd418a07b1faae48e12a7fa01e67b16d8bf47869' 
  AND token = 'FzO51fZA0gRQNmJ1aQ5EZJtMBV88zVr8WsyeQRdqon0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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