SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9125d62de610eb504ed065431982da56af9553f5cfa080b1fc1ebdb9ded1896c' 
  AND token = 'JOrEojRJUGGOIxCmTXba10+vPYRjl/B2kh1ONkzkotI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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