SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '79577e06084a193d124d93ac1753a323ddfe80d6e900a005a9ede29473e3dee1' 
  AND token = 'ryKo3oJq67YS3bSY+GbaIQ2Yuz+W/Kp8lVNndaRrjEI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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