SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1208133ea772de22efc837808114cede0b4003f4f6e244c3609839fb5bbf3de1' 
  AND token = 'dKaDD7FHrbFMQcQEZtU5XUfTnDB4yjUba39PHtEID+8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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