SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60eca3ac342a25814d80a9c7f0dcbf0208bd2e04a9a645abeefcfec7d97686e1' 
  AND token = 'nyNAzXPjbp8DMLHVbJE/Uj1SHmYOtIfloS/kigmpPKY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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