SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '72e994243a35da23501bf41bd534eddf12727bf0c5a1ccb32919793278a94286' 
  AND token = 'yLmURkd8muxQVs32Hs/Cb1lyLdEwm2VMibRWlhj7uX8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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