SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8a7edd79c13a303e8f3b62c39550f18335a724293ba3ce177baa3c65c268b199' 
  AND token = 'VGTsZg+TUUBgiMpZZrrAw/S7TA6xpEtfnmbvANO7ITc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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