SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fafdd6755e22f1296d64aebd57f1fad893ef1e877c2952589f93d26de9c4e5d7' 
  AND token = 'aY6OEII/A8pHp3mt4rdaSaxXkgTmEYsWmHNX31VOvUs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00061

JSON explain

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