SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '81c1ec89a4ed767c44d9d8e393795dd7946e752ff67a7aded081d0774426af97' 
  AND token = 'BfxaxphzxiHP6zyyAiLw4TgdOxyBaIK9K4RLUJrU4Pk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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