SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd11dedd0f83e22e840d639e20fd8491972ec22085b8afdbd34224e54e65972a4' 
  AND token = '/NLdkJ+X1fSj1LcCLuye5ukamd4lvIYXE78icjdk01E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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