SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48cbe2a3075884839669099e33a5dc83f23e7b217a2d148b01d1af71e5763ecc' 
  AND token = '1o+hTU0PGzRrOBSnVNVE4xUqD3ANvAL0lIC/5KMfqrg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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