SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '978d1c17a20c2b205dc85f11bc116612db2efba297a0e58741108f37bc8b00cf' 
  AND token = 'In3HUwrI/iH3+xaWvQvPDNvxoUdfxOuk9Ry2wIk9/KQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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