SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7888b4225d57235d5f4b7768b8201bfa1418961580c0ac639c1344e173862e8' 
  AND token = 'xoNbGZokeFnfdh3LGp9oJBSVG9dILQUuqVSlbEHbhjM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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