SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '14c5f54ab3d979d6ea42225b95c2e080329e89545f8130b6bdb85cd1b65d3346' 
  AND token = 'g4lvpwOyJ42NuBG6AF6KXSre+ww3/JS2GsDkqjm+Ut8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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