SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '36cc4209da06093844d0b06b20edecc08337f7ac5bd538ad89f31acfa3514131' 
  AND token = 'Oh3Nd6on3CLUZ0lluIUTNWjZChn4SNuAVZxlqYAk0wA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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