SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e6ed06fa4247da05fcfbfdaca9c1ceda9c195af71d5e02efa89b478ad5c8bcc3' 
  AND token = 'aWIhDOap95aXc5rAdF7GSOdXItZpPXZCub5AsDuMyEc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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