SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da990563bc399c39b0b830567791ffe5a2ee77c0c774f80694523bc6ace38542' 
  AND token = 'D/r+z8b/5RnBnc5KrdLDCxnC22WkgvnCYFARGI4HLAU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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