SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd13860d133eb15e22c21262f5b8c6e63fe019fed795e264bfe90fd02b1428f7' 
  AND token = 'XdZL/CquioN+/45UQUNsb6lb64ctH8aeLjbSMU53Lvg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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