SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'dcea275c68f21be4727da2c3b380888d71d426be6ee7dae8d14bbc0c4776bdd4' 
  AND token = '5FWHGZHUxXUAllvVMmZvPjAj0Ec/hyxGTNOpEuYm9o4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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