SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c76c1f8caea3e43fd35160a766fefd05672c70af761286ac3b70f65d9e43f332' 
  AND token = 'xauVao+XevmDDUYi1aHxXRNq2iVWD+nsH8fOLtoODXQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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