SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ce0b12efe45c9305653570f59cb3203839831596fe928a61b580d0b418ab1d7' 
  AND token = 'eE0XCk4WHaU1JtECDODkagx9Ki39dW5L6AAG8sMzfPo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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