SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '094b80745cd26802c53861afcbddbf5a2b0ff6f3f8a0ac45ce6d33cf8bab6fa1' 
  AND token = 'KujAiBpTAAsXbFysT2ndSqbjxCJLOa0EPIOMiNLH1i0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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