SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '78730672810babc086a0b0bd1bdf55452086ca973bfe50dbed32c94ae33702c5' 
  AND token = 'aegnUrPv2aEmaNKkPeYnY4QOFXC7Qts1gkCx01SXnE0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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