SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64aefd407fac9ab035ba8166cad9ba5fd5631fa975a97250342c066a10683fa5' 
  AND token = 'jXJhGN1v5NK7T8LwO+mwpQFYobRljPJiZjwfYeCMQbc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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