SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa0c97909dbaf7d5c350ff2eaf278084b04eb12b55b04dd711cde73810841f49' 
  AND token = 'DBP9g1DcHi1rELoxPNDIGujQwec/eFJ37j7ihaCT0OQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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