SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10d6e1cd5ef7076a80b287cbf3baa759be80cc01d9d7c56b83cbabc0978b6a61' 
  AND token = 'Eok37hnmg1Y5TMHHXYAa76kADKTF+MuynH3WGTnTIro=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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