SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d8abe98d9765326dc3dd0f54cdfd2280ee3165023060e3cc196b98553a15a17' 
  AND token = 'rqlaRnnfRZwfxBf3YYBA3I94mzoSBHJ7pH2ZbDLyxUk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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