SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '46fc2eb251731debd7d8179c207112722adbc4c55bf927a9276e806bc9009983' 
  AND token = 'zhXyfMTgv6CtPj9tJ8Cjofz0krIw0AeAk/UczaRXwc4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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