SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9bc7452b4f66cc46e5d22fa909deab825166811ad3171c05e9509e82bc1feb1' 
  AND token = '2RGzfSUZy2XSyGeIG2ijRS8S9R/NdYpieYqc8eAA6hY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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