SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba31373b390510e65bb18475b8f1f157b7c399d4f8a81f18844ceaaded26d4af' 
  AND token = 'OmtTx0mWcH1MKyDSclykhjibivsMbJeVWSwjrLYOoPI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00072

JSON explain

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