SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9d11695a25fe673bf30122f70fe961db81df4d240de34fd8481ee4bf89e3e901' 
  AND token = 'a38gfIQIIXFNiPSaa3yULcpKp/H2GKwrDGNWkydFVms=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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