SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58c730eb1634525a2a6cfc81590d7154cfcc0151b214cc0248c0622a3f88c764' 
  AND token = 'LhQ+Xm50bmKdQxLH3dioZS5kCl4WD1FjCxULDTf8yEM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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