SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3fef9d40057927bf33fe181c8ba6e7946d254058387da0bc88a13600db038bc3' 
  AND token = 'obz0FDfOc/jc6URdr6rMI2GfKNmdcyHoldnt89WJBGY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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