SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '039d2384d752f577383d8d5e4bf9537f161211cc6691fed25c5fdb3246067fa6' 
  AND token = 'pSP9oSfT1kYMfgVL+33eVBPZJhuEAhjJZrEhhC8vNjk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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