SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64ac5cc072f6ea9a60c5786a263ecd9153b90a71615f36a9e4b55dcb80add17b' 
  AND token = 'pGpERd5QB5VALSJiKNlX01PZECQTv9wmLrPHvXDcwT8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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