SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df180e2d558ff4e7c719fcb7d52528149f1d0b7683080f400065cd63bb829b45' 
  AND token = 'ovcO43mlnGeq62qg5oDT9zBjgOCIEhxfcXU0FlptAII=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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