SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c7e40ca829b43dd4a957cab23c79fb57e0eff8b0fb0284cddc445dd95665382' 
  AND token = 'C53lMJifNYjhfDBDUEXtGeSIhBa0C9lw/a80G3Dj8bU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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