SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5643355ea89af3dee6a2ffbfa93f7c21f38dd5c009c98789fe1a12eaa922fac1' 
  AND token = 'I6odvWBNKpc52Z7HsE82OVrtEJTtarf4eb96hwj0jbY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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