SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1aa86dc54ee5f1beec10964741fd00494537109a039e55088668475b96ab06c1' 
  AND token = 'giL3CsME+j0zt2UzYqFO5Glhdpn3uZPR73lrPzdovKs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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