SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d617eb7b26f242512fda9481c6a7c5f014297d0e8bc634f4c55a46d1618bb85' 
  AND token = 'B0lgxvcG7Faghnuo0P/9B5ssXwe71HqOyrvzUmSJpEo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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