SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f4357a2356f562435cb99ed0c4db6bca194aa7582fe453c90499978e906806ca' 
  AND token = 'AhwjAUfmvOH9Heb8KjEH4xVLuRLhAsq38n4MLDGpc3w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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