SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c32f20129a641341ff1f076e89555bd37fec0c71068545c8e9018b868aa7f53b' 
  AND token = 'yBVXBO686QCi7zrQtHz9a6wvJAaxlguWYKyh49VDVXc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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