SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '96ed7c3defe18175fecb7c0266d65d95e182e3c25001844ac8f00e35192f8ee8' 
  AND token = 'xK2PgFTS1O3rRhLL0BinC4Yv6h8rmd1QJsauA/+pgMg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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