SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e52af178185318aaeb91aebb5930276a8b41114eeb2132a77fcd859f39d3ae75' 
  AND token = '06FUGDKcKy8MygQhk1Hlm/Jd4AfUoKJP8JgbbLcyfgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}