SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cdfba50a8dc2e1c70fc58f33ae03629aba91b2510ca77ba962fd6f0ed862fd93' 
  AND token = 'h/jB9g7ndTlH+aBVa+qpsYsPZz1pHiHMWHymgj9S6Yo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}