SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ca0e71b2dedd7e09d0584ead3042218d1a5988eee71675513c1818034bb949b' 
  AND token = 'Dw2fAJhdvnhhEtncqb90oG1rNAUiaZfmsb2ODVhUtuY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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