SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c69fea5412f6ebc1629ba8dac508acd0982d25052bd24a945a2b51bf618a276' 
  AND token = 'BQUxLkz3OoTZTijNPtUUj8zDzr0VEM4RWgZMs1xrdSc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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