SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7769d4bf441c8771e020a106737ef462d05e331279e67d026c4f96d165fc53f9' 
  AND token = '10ufc1y3A1CuFGq7LGZ1Xe+4axfeWXnAI5L5bsvo61c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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