SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8dc67530f1c17e17bf32315fec4bbca17d3c782285b00b2f2096be8ff680878b' 
  AND token = 'yrPiw2Ndoy91MU/PquoK0tkUuMRUYCo4c4r2gU/59fI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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