SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4d3bbefb58cd96b963762aabe6005009710b0f407c354c7faa2e2794a6be53e8' 
  AND token = 'g51dhKau/qv0YAAoyRho1OgVpDtxK5sULG/z+CnBAKs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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