SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9e31d2ea4923ad4d1f04998127993dbb0ad81d61b733097e2352cbc0be05e28' 
  AND token = 'YObtGNlX+0dmb0qp9/ehuxuqgNneTiXmqMBhjVtg0XE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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