SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3e49bf7cf3156d46f30316fc11cdac73c86a960b29ed4085bd95bc20c5372630' 
  AND token = 'aHCmQXXdpnyIKkCHQwk1WNi3JZXHYDoOICOtn8BMbCo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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