SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '625e82ba2dc0aab11a05f325dc17798ee4c17a62f9e4af1efce3e48024d9a463' 
  AND token = 'G6JT4ot3gJ5FpuZd/wfOermBl8vGaFj82pPZmlB7ESE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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