SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'acfcc7c491f0fbb26308a64be4481b406598318c7b66e5df68aa92894eac21c8' 
  AND token = 'uQx1ADLzsIIGPKeckxnoCC1FDdndKCNU0AH294oxFho=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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