SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a3b6677ac1054b17c0f8f6523b6384d93055147604e60d9a98c841ee35bb5f7' 
  AND token = 'wicfa4xjcIMqr0d9eWJgoKTwJeAIPDNdy0nZxbBQaLs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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