SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e252b61e73ba3334b788568d3ffc8344432b39603cdbdd08c06bdbf4c7fcc479' 
  AND token = 't4SWSthWmXB7uaLQdLI2hZsco6wYvkxou/NI2h32pMs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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