SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f4cef5aaee372b088292b1840dc08d1b09a57cce7dde8dd17891f4a467d852b5' 
  AND token = 'dm+MaIIFxW/nylU9n03P2e2hCFix874G5UYtxYGvrfo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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