SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4a21e3de4bc8dbdc07b1633e687738abb26bf152c8bb06e3f476dace26694aa2' 
  AND token = 'rg0Qzls/BfJWnBrVvdkHCFXTZVxaGslVSEEnwCldVb8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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