SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ab53f1e0a62fca386aa2df99d2192688b98a744131e0ebd4080d975faa1be374' 
  AND token = 'UC+lyLShuynBBDwPhqKS3Mk6NFlfEbhEV6ZWtvXPioE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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