SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ccadacfbce6500a77434f1d1fcb00ed849b3ab472e6573d6f7665ba1647c7e2' 
  AND token = '2gOmnScgykYvO5ijgASlgAcBsV9JpnSlan1BdeZ+M14=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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