SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'ba9049ee850e5124345cf4b83416ad5ed081db004504033beef37a143f90d9c9' 
  AND token = 'RkTyRN6kbJlySmPPQpYXpxE7aa0Hy0gNIbVISxFrwVE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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