SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c616f691f0d637be45e56ca7b004d3be8d6b908d61c831cd0714978ff3cbc2be' 
  AND token = 'IjXjCBcYjL4+0r6dqsdaOvGsxYi+/gH/pRYP22DJDaU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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