SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3653214277ea32514fcab693d78750966f2133f348f446d04936b01991a8bd69' 
  AND token = 'vULi4GQsAjqyjXoo9YobtZUyYnH/HVFDvM37AIFwzBU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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