SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '954af4b4c8b815e6567f663e822b3f886e1061bddd4088dd27f9ec8b531b7597' 
  AND token = 'W3fX9aVHrupUfYPzdwgOpMP9mktfOsQF2F8GUuMGdeM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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