SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aaaa1e7d505172482a34657029b1c358f1bf3352897543114783f8422540918e' 
  AND token = 'tCwx8x1LMfn73GX+5DIFsSFeG7zDku1W2Tf3/kpB/5E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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