SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '99fdda172a8bcc3c73578ac77a93e6f02ddc253bf23b21863016db9bfaca79e6' 
  AND token = 'rrntAHa9TTLHw25+gGOsDp/ORNodVkNbyOHjPbX9T1Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}