SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ffb93ea71affe1de6893a75d8734f46742820895bded9b6094b99ddab77e20c1' 
  AND token = 'W00CnzmyxGIiU7Qkjz32qECP+YbP/tb0xsqa0ZDH84w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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