SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '2c0c620555068a41d712e5bb5b18aa317b3ad73a27995c5e52e92eeb68840944' 
  AND token = '0FFpHpV0vIxTP/7afwuHsLjXhY1Y1BNNetUKo8BNUVo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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