SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5e989c0216408fec4ebe662fe3c9dcbb4373130aa7b089112ff508af91de8ac8' 
  AND token = 'UYZe2m2HAyMp9C8SZ2VBECgxDP3MzDkbPYC0UFpBz+4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}