SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d96b5eb1dcaf82b3a52f20f7d7924acb97f6669ca126ded79cdc860963e4579' 
  AND token = 'YqYpEOu9GsPmR4rQJoW9Dqn+fZkhQmyMVWqbzqc31WY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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