SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4fcdae30bc2eb9cf3f5703ed2c860918a07ad8b93149a877fc8934eda8bf184e' 
  AND token = 'Ghz9StOy7kRZ7P3gXYjxEGCKIvjU/IY2IH1rUtxv9mM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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