SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '087f8c83f6671d9fa9746eb3181a82d97f5af917de832e4228b3aadcc9147fa1' 
  AND token = 'hitEKwfT34hvfVB5EupDFmHU1oJZuO+wPQ2BobILzOs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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