SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c7d63cb6886e22029b5f3244b32cf2350077075032e37c57730d6cf71488ace0' 
  AND token = 'CSX+r4iHiyyRhuBQH/6imba1DjzSrQAEyOZMYozsCkA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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