SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea4b12aaa1ba22b217cc1aba0d9fd38c54a76f485386e46fee9fd1d598cc998a' 
  AND token = '/znXSBSVINzYNLR1tr35y2c+VvLw99fqYZwjZWU+OeY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00058

JSON explain

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