SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f542a61445ceca1aab9b616410cfe19ea76df22e8edbf33815595a4b8e07f9aa' 
  AND token = 'HrUWiZv2rPJJL3jrSNLR0GwU22MVyN5w2aWuzVU3Sxo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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