SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3ec91055da360fb9669a848349272cc79ae5820b9b6272e5752146f734aeca88' 
  AND token = 'L+nd0PitnIH3+rwyTXj8YougFFFPXI/QmKBsqjcSEX4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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