SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b04b551124d6fea5aba0491d720fc47a7c117a0ecea54702f7c756806fb51901' 
  AND token = 'z9Qu1IYfY4PDeCMU9UgRVooSWHEp6em/qv2DCpDaPmw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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