SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6966ff2d1c9b0448c9c7ee63aa3aae0794952d7be8eebab87748bf141309d9ed' 
  AND token = 'uRXAPaC+QvMoi4J6Jn3M86Wcz3pICTHL2eBMXxKwOaQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}