SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '06174841e5bfff4811145e84f0abb51c9171c790b4dc707e385072f9ddb17981' 
  AND token = 'MC8xt3r0qpMrbeXuLjLho6TJ/OiXplrz6ZkRNnp/OEY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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