SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4d1709420be2f14add56f0797e8470cb3763e27de6ab7c258472fa59f58e48a8' 
  AND token = 'bxstrFkujzHJwA+gX+M9f49hXCZ2fUo94jW9R8CSilw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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