SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a14c3f0432c713af2f9cf78befd9a2b3c7c2a86945c3406dcda89b2544742f23' 
  AND token = 'peaD7kDqWTLQp9Y2sTHiUrZw4new0sh3ygT7ZMA5l2s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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