SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4295a978cfcbb5c847f82a8e12dfa12835c3d0a2a6ed8257b1258f13ad884c98' 
  AND token = 'SgS1mx7QnAzvIS81zoahaKnDVxTN1TdN3QPnW+sjd98=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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