SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '91b16854907c725e1a7b32048dd73bba65ac91b9cdcd9e42f79291cdf04c49ab' 
  AND token = 'ry1Qgm9HriYTGZM9XVffq9Spyo/KKWuKE3XVID1bbII=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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