SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd94e91c052856b70789041da7b3031f27c0196001e743e9bd5aa477763b48ecd' 
  AND token = 'tuG3VCBtYgVMgqxj5n51Ztj/7TbwCOKxFAeQcnEw4NY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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