SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '2a261f372f31cf1a45208f79b5d48516832320ffbeb26d23661a0f602982d6f1' 
  AND token = 'YbWCe5FCuITst0AI6/T3mKbzJu3xOxSpWVa/AKjvzgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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