SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1991b55039d0d13eb68cc4161a26b0359afa524f7b965df0b30ca48e2dd95067' 
  AND token = 'aPNBmh+zEKSAvXnzrdPvyknxmpDfdGEP1F1GUcIR7Qw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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